Copper has been used in wires for over 130 years, as it is a highly efficient conductor of electricity. Today’s wires have insulation coverings made out of plastic or thermoplastic, which provides a long, durable life. Many older wires used cloth insulation. Rubber was also common, but is not used as much anymore, since it becomes brittle and deteriorates over time. Eventually, old insulation starts to flake and separate from the copper, leaving the wire exposed to the outside environment. As consequence, short circuits, electrical arcs, overheating, contact with moisture, or contact with other energized wires may occur. This in turn may cause ignition, followed by an electrical fire. For this reason we recommend that you have a qualified electrician perform an inspection of your property’s electrical system including all wiring.